(1) Field of the Invention
The present invention relates to a communication apparatus, and more particularly, to a communication apparatus for controlling communications of electronic mail.
(2) Description of the Related Art
Electronic mail includes text mail, voice mail, etc., and with recent popularization of portable telephones (including PHS), more and more users have come to use electronic mail as a typical tool for communicating information.
Meanwhile, portable telephones, which are small in size because portability is an important factor determining their design, are equipped only with a small-sized display and several operation buttons and thus are not suited for sending complicated information by text mail. In recent years, therefore, voice mail is widely used in which information is registered in the form of voice and a recipient is notified of the information by voice.
Voice mail is a service whereby speech on the telephone is stored in a server to allow exchange of vocal information between users. Conventional voice mail services can be classified into two types: a type wherein a registered voice message is encoded to generate voice data, which is then transmitted to the recipient at a specified time and decoded and replayed at the recipient side, and a type wherein a recipient inquires of the server whether any mail has arrived, and can listen to a voice message, if any, as in telephone answering service.
In the former case of transmitting a voice message in the form of voice data, however, since a voice message is large in data size, a correspondingly large channel capacity is required to receive voice data. Also, if the receiver side is not equipped with the function of storing, decoding and replaying voice data, the recipient is unable to enjoy this type of service. In the latter type of service similar to the telephone answering service, the recipient needs to inquire of the server whether any mail has arrived, and therefore, this type of service is inferior in terms of convenience.
There has also been proposed, in Unexamined Japanese Patent Publication No. 2000-32139, a technique of equipping a server with a speech recognition apparatus such that a voice message input by voice is converted into text, which is then transmitted to a recipient side as text mail.
However, even with this conventional technique, if the amount of information contained in a voice message is large, the size of the converted text correspondingly increases, with the result that the text fails to be fully displayed on the display of a portable telephone or the like. A problem therefore arises in that the advantage of registering an originator's message by voice cannot be made full use of.